Internal combustion engine



Feb. 1, 1938.

' P. IL'ORANGE 2,106,914

' INTERNAL COMBUSTION ENGINE Filed Dec. 24, 1934 F/GJ fnvznfan' 2 Sheets-Sheet 1 Feb. 1, 1938. P. LORANGE INTERNAL I COMBUST ION ENG INE Filed Dec. 24, 1934' 2 Sheets-Sheet 2 Patented Feb. 1, 1938 UNITED STATES PATENT OFFICE 7 2,106,914 INTERNAL COMBUSTION ENGINE Prosper LOrange, Stuttgart-Feuerbach,

Germany Application December 24, 1934, Serial No. 159.005

10lalm.

' forced by the pressure into the cylinder.

1" Oil. The object of the present invention is to remedy,

In known engines of this kind the fuel is generally injected into the pre-combustion chamber by means of a pump which requires a very exact regulation and which, in the case of small engines, becomes dearer than the engine itself. .An

elimination of the pump is therefore desirable.

It has already been proposed to eliminate the pump by utilizing the suction of the engine for feeding fuel direct into the pre-combustion chamber. With this arrangement the fuel arrives in, the .pre-combustion chamber before the actual firing thereof, audit will in the meantime. be partially decomposed and-coked by the heat of the chamber. Thus the'construction is not suitable foruse in engines running on heavy this defect, and the invention consists essentially in the provision of a'fuel receptacle which receives the fuel by suction or injection and which communicates by means of ducts at one end with the pre-combustion'cham'berand at the other end with the cylinder, a check valve being provided in the fuel supply passage so that the receptacle will be acted upon by the air compression for feeding fuel into the pre-combustion chamber, and by the pressure in the latter for feeding fuel into the cylinder.

Theduct leading to the combustion chamber is smaller than the duct leading to the cylinder and delivers the fuel into the chamber-in the form of ajet fine enough to effect the necessary atomization of the fuel. Preferably the ducts are arranged so as to open into the ends of the passag which connects the pre-combustion chamber with the cylinder.

The firing of the gas mixture in the pre-combustionchamber is brought about in any suitable manner, for instance by electric sparks, by heating the chamber, or by the compression heat alone. The ignition can be facilitated by allowing traces of fuel to be sucked into the cylinder,

In Germany December 7,1933

The passage which connects the combustion chamber with the cylinder is preferably in the form of a Venturi passage, i. e., it diverges from the middle towards the ends.

7 The pre-combination chamber can be spherical or cylindrical or have any. other suitable form.

It may either be made in one piece with a cylinder head'or form a detachable unit. It may ,be cooled or heated as required. Heating of the chamber may be resorted to for facilitating the 10 starting. In the case of a small engine, the heating can be conveniently effected by means of an electric heating element. Thecharnber may have an inset or lining composed of iron, nickel, copper, either alone or in alloys of chromium, tungsten, beryllium, or the like. The heatin may be applied to the inset'or lining. The fuel receptacle can have the form of a bore or channel made inthe cylinder head parallel to the connecting passage between the prefore, under the influence of the air compression,

the fuel reaches the injection noimle.

The check valve or valv'es arranged behind the receptacle may be accommodated either in the cylinder head or in a separate fitting.

The invention is illustrated in the accompanying drawings,

Fig. 1 representing a general diagram of the arrangement, 1

Figs. 2a to2d, a series of diagrams illustrating the action taking place in the fuel receptacle, Fig. 3, a sectional view of a cylinder head constructed according to the invention, and

Fig. 4, an enlarged sectional view of. a modified form of fuel receptacle.

7 Fig. 1 shows a cylinder A connected to a precombustion chamber B by a Venturi passage 0.

G is an elongated fuel receptacle one end of which communicates with the chamber B, through a duct D, the other end of the receptacle being in communication with the cylinder A through a duct F. Preferably the ducts open into the ends of the passage C where the latter merges into the chamber andinto the cylinder respectively. The

nular cross-section. Aeasing V, whichis screwed 'the tank is therefore connected through a'check valve N and a pipe M to the cylinder A, so that gas pressure will be applied to the tank, for instance just before the exhaust port is open. for feeding fuel into the receptacle G; The tank may be provided with a safety valve.

[The action takingplace in the receptacle G is illustratedinl igs.2atofld."lhedilgfaml"ig. 2a shows the receptacle empty. During the suction or exhaust stroke, according to the arrangement, fuel will be fed into thereceptacle as shown in the diagram Fig. 22:. At the end of the compression'stroke fuel will be forced from the receptacie G into the pre-combustion chamber and atomlaedin theiatter, asindicatedindiagram Fig.2c. The timingof'thisfueliniectionwill be determined by the'leng'th of the duct and by the resistance offered thereby to the passage of the fuel. On the explosion of the. fuel mixture in the pro-combustion chamber, pressure in the latter increases and forces all the fuel remaining in the receptacle into the cylinder. This is illustrated in diagram Fig. 24. The receptacle will then be entirely clear, as shown in diagram Fig. 2a, and only the passage between thevreceptacleandthecheckv'alve-Iwillremainchargedwith fuel.

The constructional details of a small engine is illustrated in Pig. 3.

The cylinder A has a detachable head it in which the pre-combustion chamber 3, the Venturi passage 0 and the fuel receptacle G are formed. The chamber 8 is bounded at the far end by a cover 8 which is clamped in position by a screw cap T 'appled to a reduced portion of the head R. Behind the cover 8 an electric heating spiral P is arranged. The outer end-of this spiral is connected tothescrewcaplandtheinnerend is held in aninsulating block I. The cover 8 is made of material which is beam! and which may in addition have a catalytic effect. j

Thefuel receptacle 0 has the form of a bore inwhlch ailllingmembero'is supportediby means of a screw threaded head. the filling memberbeingadaptedtoproduceareceptacle of aninto the headR contains the check valve J and tn regulating valve K and is formed with a 'screw connection Q for attachment to the fuel tank.

The regulating valve K is a simple needle valve. Instead of employing the screw adjustment shown in the drawings, the valve may becontrolied bya governor or, in the case of an engine of greatly variable speed, it may be controlled in known mannerby the under pressure inthe induction pipe." The fuel supply to the receptacle G is regulated in accordance with the required power output. Usually the amount of fuel injected into 7 the pre-combustion chamber is uniformyand only that injected into the cylinder is variable.

Fig.4 shows-a modification of the filling memberfor the fuel receptacle G. the member 0' be-" ing made of the same diameter as the bore and provided with a screw thread U forming a hell cal fuel passage'which maybe varied in form and length to produce the required resistance.

In order to effect a rapid rise in the pressure at the end of the compression stroke, the piston may be provided in known manner with a projection adaptedgto enter the connecting passage C. Alternatively a by-pass leading from the chamber into cylinder wall may be closed just before the end 0 the compression stroke in order to effect the sudden rise in the pressure. Generally. however. the regulation of the injection and the timing thereof can be effected by a suit+ able dimensioning and positioning of the ducts D and 1". 1 I

I claimr An internal-combustion engine of the character described, comprising a cylinder, a head on said cylinder provided with a pre-combustion chamber and with s Venturi e connecting said chamber with the cylinder, an elongated fuel receptacle in said head arranged close to the Venturl passage'and parallel to the axis thereof,'ducts;, connecting oppomte ends of said receptacle with opposite end portions of the Venturi e, a fuel supply passage leading to the receptacle, means for feeding fuel to the receptacle through said supply passage after each explosion. and a; check valve controlling said latter passage and enabling the receptacle to be influenced by the air compression in the cylinder for feeding fuel into, the ire-combustion chamber and by the explosion in the latter for feeding fuel into the cy dei'. the duct located near the rare-combustionchamber being narrow than the duct located, .near the cylinder-for preventingthe receptacle from being completely emptied into the precombustion chamber. I

, ritosrsn L'ORANGE. 

